The present invention relates generally to a wireless communications system and particularly to transportable infrastructure that enables a wireless communications system to provide service to areas that are not served by conventional terrestrial wireless stations.
The increasing need for communications networks and capabilities in outlying and geographically diverse locations has created greater demand for cellular systems. Many new carriers providing the infrastructure for such systems have focused their resources on building as many terrestrial cell stations as possible to expand their respective areas of coverage and consequently generate more revenue.
However, the buildout rate for the terrestrial cell stations is typically slow and expensive, especially in mountainous or otherwise difficult to access areas. In addition, in some these areas, a carrier""s return on investment may not provide the incentive necessary for the carrier to build the necessary cell stations, thereby leaving these areas with either limited or no cellular service at all. Further, many areas having a sufficient number of cellular communications base transceiving stations to handle calls during both off-peak and peak times cannot adequately handle large volumes of calls during sporting events or other short-term special events that temporarily attract large crowds. In addition, in remote geographic areas, in areas that have been hit by natural disaster, or in areas that have been transformed into, for example, a military theater, terrestrial cell stations may not be available within the given terrestrial range necessary to establish communication links with the airborne repeater, thereby limiting the overall effectiveness of the system.
Satellites represent one possible solution to the above system needs. However, because satellites must be developed far in advance of providing the contemplated service, it is difficult to predict the future service and bandwidth needs that may be required in target localized areas. In addition, because the above-discussed events are highly localized, satellite-based service would be inefficient, expensive and would very likely not be able to provide the necessary bandwidth to support the local traffic load.
Non-commercial airborne cellular systems have also been proposed in which a cellular repeater mounted in an airplane flying a predetermined flight pattern over a geographic area requiring cellular coverage backhauls calls from cellular phones within the covered geographic area to terrestrial base stations spread across the footprint. Because the airplane is capable of traversing geographic limitations and takes the place of the cell stations, such a system overcomes the above-mentioned limitations of conventional terrestrial cellular systems.
Nonetheless, an aircraft-based wireless system utilizing conventional base transceiving stations still may have certain limitations associated with its potential areas of coverage. For example, one currently-proposed airborne system requires that the airplane in which the repeater is located fly at high altitudes, therefore requiring costly special equipment for both airplane and pilots as well as pilots with special high altitude training. Clearly a need exists for solutions to the aforementioned problems.